Conventionally, as punching machines, a work head thereof comprising a ram and a tool is moved in the direction of axis Y, and a work clamp apparatus thereof clamping a work is moved in the direction of axis X, thereby, a work can be punched. This kind of punching machines are known in, for example, a Japanese Patent Publication No. 59-44938, a Japanese Patent Publication No. 59-45449 and so on.
According to this type of punching machine, in order to punch a thin and long work which is punched with few holes, it is necessary to punch the work at high speed. In such high-speed punching, there is a problem how to move the work clamp apparatus in the direction of axis X.
For example, it is very difficult to move at high speed a work of which dimension is 5,000.times.450 mm and thickness is 0.4 mm, in the directions of axis X and Y. Especially, it is difficult to move the work in the direction of the shorter dimension thereof.
In order to avoid for moving the work in the direction of the shorter dimension, the work head comprising the ram and the tool is moved in the direction of axis Y. However, when a work clamp apparatus is moved at high speed in the direction of axis X, the work head and the work clamp apparatus are interfered with each other, which are in a dangerous state. Further, a dead zone exists so that it is not possible to punch the work. Furthermore, there is a problem that it is not possible to use a tool of a plurality of tools in the work head, located farthest from the work clamp apparatus.